Cardiovascular System
heart and blood vessels
Tainted Love…?
Systemic
Circulation –
delivers blood to
all body cells
and carries
away waste
Pulmonary
Circulation –
eliminates
carbon dioxide
and oxygenates
blood (lung
Structure of the Heart
Heart Size – about 14
cm x 9 cm (the size of
a fist).
Located in the
mediastinum (space
between lungs,
backbone, sternum),
between the 2nd rib and
the 5th intercostal
space.
Fibrous Pericardium encloses the heart (like
a bag) and has 2 layers
●visceral pericardium (inner)
●and parietal pericardium (outer, attached
to diaphragm, sternum and vertebrae)
Pericardial cavity – contains fluid for the
heart to float in, reducing friction
Wall of the Heart
Epicardium – outer layer, reduces friction
Myocardium – middle layer, mostly cardiac
muscle
Endocardium – thin inner lining, within chambers
of the heart
Heart Chambers & Valves
●Your heart is a double pump. Circulation
is a double circuit: Pulmonary (lungs
only) and systemic (rest of the body)
●Heart has 4 chambers:
o 2 Atria – thin upper chambers that receive blood
returning to the heart through veins.. Right and
Left Atrium
o 2 Ventricles – thick, muscular lower chambers.
Receive blood from the atria above them. Force
(pump) blood out of the heart through arteries.
Right and left ventricle.
●Septum – separates the right and left sides of
●Valves of the Heart – allow one-way flow
of blood.
4 total
●(2 Atrioventricular Valves (AV) & 2
Semilunar valves)
o Left Atrioventricular valve – also called the
bicuspid valve or mitral valve. Between left atrium
and ventricle
o Right Atrioventricular valve – also called the
tricuspid valve. Between right atrium and ventricle
●Aortic Semilunar – or just aortic valve.
Between the left ventricle and the aorta
●Pulmonary Semilunar, or just pulmonary
valve. Between the left ventricle and the aorta
Mitral = bicuspid (left side)
Tricuspid (right side)
Aortic and Pulmonary are
both semilunar valves
Path of Blood Flow
*This is a good time to watch some of
the heart animations and tutorials.
Label the heart
diagram on your
notes!
Check your labels!
Name the
valves
(#5 is not a
valve)
1 Pulmonary Valve
2 Tricuspid Valve
3 Mitral (Bicuspid)
Valve
4 Aortic Valve
5 Heart Apex